THE SECURITIES REPRESENTED HEREBYHAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT, OR UNDER THE SECURITIES LAWSOF CERTAIN STATES. THESE SECURITIES MAY NOT BE OFFERED, SOLD OR OTHERWISETRANSFERRED, PLEDGED OR HYPOTHECATED EXCEPT AS PERMITTED UNDER THE SECURITIESACT AND APPLICABLE STATE SECURITIES LAWS PURSUANT TO REGISTRATION OR ANEXEMPTION THEREFROM.  PARTY B MAY REQUIREAN OPINION OF COUNSEL SATISFACTORY TO PARTY B THAT SUCH OFFER, SALE ORTRANSFER, PLEDGE OR HYPOTHECATION OTHERWISE COMPLIES WITH THE SECURITIES ACTAND ANY APPLICABLE STATE SECURITIES LAWS.

December 17, 2003

Mentor Corporation201 Mentor DriveSanta Barbara, CA 93111Attention:  Chief Financial Officer

 

Credit Suisse First Boston InternationalOne Cabot SquareLondon E14 4QJEngland 

Dear Sirs:

The purpose of this letter agreement (this "**Confirmation**")is to confirm the terms and conditions of the Transaction entered into betweenParty A and Party B through the Agent on the Trade Date specified below (the"**Transaction**"). This Confirmation constitutes a "Confirmation" as referred toin the Agreement specified below.

1.         The definitions and provisionscontained in the 1996 ISDA Equity Derivatives Definitions (the "**EquityDefinitions**") and in the 2000 ISDA Definitions (the "**SwapDefinitions**" and, together with the Equity Definitions, the "**Definitions**")(in each case as published by the International Swaps and DerivativesAssociation, Inc.) are incorporated into this Confirmation.  In the event of any inconsistency between theEquity Definitions and the Swap Definitions, the Equity Definitions willgovern, and between the Definitions and this Confirmation, this Confirmationwill prevail.  References herein to a"Transaction" shall be deemed to be references to an "ShareOption Transaction" for the purposes of the Equity Definitions and to a"Swap Transaction" for the purposes of the Swap Definitions.  For purposes ofthis Transaction, "Warrant Style", "Warrant Type","Number of Warrants" and "Warrant Entitlement" (each asdefined below) shall be used herein as if such terms were referred to as"Option Style", "Option Type", "Number ofOptions" and "Option Entitlement", respectively, in theDefinitions.

            This Confirmation (together with allother Confirmations of Share Transactions between Party A and Party B withrespect to Shares of the Issuer contemporaneously or previously entered intobetween them, notwithstanding anything to the contrary therein) shallsupplement, form a part of, and be subject to an ISDA 1992 Master Agreement (Multicurrency- Cross Border) (the "**Agreement**"), as if, on the TradeDate of the first such Transaction between Party A and Party B, they hadexecuted the Agreement (without any Schedule thereto) and specified that (1)the Automatic Early Termination provisions contained in Section 6(a) of suchAgreement would apply, (2) Second Method and Loss would apply, (3) suchAgreement would cover only Share Transactions with respect to Shares of theIssuer referred to herein and (4) for purposes of Section 2(c) of such Agreement,references to payments of amounts denominated in the same currency shall bedeemed to include references to deliveries of Shares issued by the Issuer, andSection 2(c)(ii) of such Agreement would not apply.  

            The Agreement and each Confirmationthereunder will be governed by and construed in accordance with New York lawwithout reference to choice of law doctrine and each party hereby submits tothe jurisdiction of the Courts of the State of New York. 

**            In this Confirmation, "PartyA" means Credit Suisse First Boston International, "Party B"means Mentor Corporation and "Agent" means Credit Suisse FirstBoston, acting through its New York branch and solely in its capacity as agentfor Party A and Party B.**

2.         The terms of the particular Transactionto which this Confirmation relates are as follows:

            GeneralTerms:

                        TradeDate:                              December17, 2003

                        WarrantStyle:                           European

                        WarrantType:                           Call

                        Seller:                                       Party B

                        Buyer:                                      Party A

Shares:                                     The sharesof the common stock of Mentor Corporation (the "**Issuer**"),par value USD 0.10 per Share (Bloomberg ticker MNT, ISIN US5871881034).

                        Numberof Warrants:                 5,121,377

                        WarrantEntitlement:                  One (1)Share per Warrant

                        StrikePrice:                              USD39.4275

                        Premium:                                  USD 11,890,813

Premium PaymentDate:            December 22, 2003 

                        Exchange:                                 New York StockExchange 

                        ClearanceSystem:                     The DepositoryTrust Company

                        

CalculationAgent:                     Party A.  The definition of "CalculationAgent" in the Equity Definitions shall be amended by deleting the secondsentence thereof and replacing it with the following:  "Whenever a Calculation Agent acts ormakes any determination, it will do so in good faith and in a reasonablemanner.  In the event of a good faitherror, and upon becoming or being made aware of such error, the CalculationAgent shall promptly correct such error (and shall not be liable for any errorpromptly corrected for any amounts greater than the actual cost of sucherror)."

            Procedurefor Exercise:

                        ExpirationTime:                        The close oftrading on the Exchange.

ExpirationDate:                        January 1,2009.

AutomaticExercise:                  Applicable,subject to Section 3(a) below.

Settlement Terms:                                 Net Share Settlement, unless Party Belects Net Cash Settlement (as defined below).

Net Share Settlement:                Subjectto Sections 3 and 4 below, unless Net Cash Settlement applies, on theSettlement Date Party B shall deliver to Party A, through the Agent, a numberof Shares equal to the Final Settlement Amount.

Net CashSettlement 

Election:                                    By no laterthan the Settlement Cutoff Date, Party B may elect, by notice in writing toParty A (given through the Agent), that Net Cash Settlement shall apply, inwhich case the Net Share Settlement terms set out above shall not apply.  If no such notice is delivered to Party A bythe Settlement Cutoff Date, the Net Share Settlement terms set out above shallapply.

Net CashSettlement:                 If Party Belects Net Cash Settlement, subject to Section 3 below, then on the SettlementDate Party B shall pay to Party A, through the Agent, the Net SettlementAmount.

SettlementDate:                        The scheduledExpiration Date, unless otherwise provided by Section 3 below.

Reference PricePeriod:             The period of twenty(20) consecutive Valid Days commencing on the date that is the 22ndExchange Business Day expected to occur prior to the scheduled Expiration Date,*provided* that if suchReference Price Period otherwise would exceed twenty (20) Exchange BusinessDays or would end after the scheduled Expiration Date due to the occurrence ofone or more Disruption Events, then such Reference Price Period shall end onsuch twentieth (20th) Exchange Business Day or on the day prior tothe scheduled Expiration Date, as applicable.

Settlement Cutoff Date:             The date that is thirty (30) daysprior to the Expiration Date.

Valid Day:                                An ExchangeBusiness Day on which there is no Disruption Event with respect to the Shares.

DisruptionEvent:                       A MarketDisruption Event as specified in Section 4.3(a)(ii) of the EquityDefinitions (determined as if this Transaction were a Cash-settled Share OptionTransaction) or a Settlement Disruption Event as specified in Section 6.5 ofthe Equity Definitions (determined as if this Transaction were aPhysically-settled Share Option Transaction).

FinalSettlement Amount:           The number of Shares, rounded up to thenearest whole Share, determined by the Calculation Agent to be equal to thequotient of (x) the related Net Settlement Amount divided by (y) the relatedReference Price.

Net SettlementAmount:             Theproduct of (x) the number of Warrants expiring on the Expiration Datemultiplied by (y) the related Final Price Differential.

Final PriceDifferential:              An amount equalto the greater of (x) the excess of the related Reference Price over the StrikePrice and (y) zero.

ReferencePrice:                       The averageof the Volume Weighted Average Prices of the Shares on the Exchange for eachValid Day falling in the Reference Price Period, *provided* that if thereare fewer than twenty Valid Days within the Reference Price Period then therelated Reference Price shall be the Calculation Agent's good faith estimate ofthe value of one (1) Share on such day.

                        VolumeWeighted 

Average Price:                          In respect of anyValid Day, the volume weighted average priceper Share as displayed under the heading "Bloomberg VWAP" on BloombergPage MNT <equity> AQR in respect of the periodfrom 9:30 a.m. to 4:00 p.m. (New York City time) on each such Valid Day, orif such Volume Weighted Average Price is not available, the Calculation Agent'sgood faith estimate of the volume weighted average price of the Shares on suchValid Day.

            Adjustments:

     Method of Adjustment:                      Calculation Agent Adjustment.  For thepurposes of Section 9.1(e)(iii) of the Equity Definitions, a regulardividend or distribution of $0.15 or less per Share per fiscal quartershall not be **deemed** an"extraordinary dividend" **andany dividend or distribution of greater than $0.15 per fiscal quarter shall bedeemed an "extraordinary dividend"**.

Extraordinary Events:

                 Consequences of Merger Events:

     (a)   Share-for-Share:                      AlternativeObligation; *provided* that notwithstanding the above, theCalculation Agent will determine if such Merger Event adjustment affects thetheoretical value of this Transaction and if so, may in its reasonablediscretion make the adjustment set forth in paragraph (A) under the definitionof "Calculation Agent Adjustment" (as defined in the EquityDefinitions) to the terms of this Transaction to reflect the characteristics(including without limitation, the volatility, dividend practice and policy andliquidity) of the New Shares.

     (b)    Share-for-Other:                       Cancellation and Payment,subject to the terms of Section 5 below.

     (c)    Share-for-Combined:                Cancellation and Payment,subject to the terms of Section 5 below.

     Delisting, Nationalization 

     or Insolvency:                                   Cancellation and Payment, subjectto the terms of Section 5 below.

3.         **Excess Share Ownership Provisions****;** **Conversion Exercise Condition; Conversion Notices:**

(a)        (1)  **Excess Share Ownership Provisions**.  Notwithstanding any other provision hereof,Party A may not exercise any Warrant hereunder, and Automatic Exercise shallnot apply with respect thereto, if the exercise of such Warrant would causeParty A to become, directly or indirectly, the beneficial owner of more than 9.9percent of the class of the Issuer's equity securities that is comprised of theShares for purposes of Section 13 of the Securities Exchange Act of 1934, asamended (in such case, an "**Excess Share Owner**").

Party A shall provide prior noticeto Party B, through the Agent, if the exercise of any Warrant hereunder wouldcause Party A to become directly or indirectly, an Excess Share Owner; *provided*that the failure of Party A to provide such notice shall not alter theeffectiveness of the provisions set forth in the preceding sentence and anypurported exercise in violation of such provisions shall be void and have noeffect.

If Party A is not permitted toexercise any Warrant because such exercise would cause Party A to become,directly or indirectly, an Excess Share Owner and Party A thereafterdisposes of Shares owned by it or any action is taken that would then permitParty A to exercise such Warrant without such exercise causing it to become,directly or indirectly, an Excess Share Owner, then Party A shall providenotice of the taking of such action to Party B, through the Agent, and suchWarrant shall then become exercisable by Party A to the extent such Warrant isotherwise exercisable hereunder.  In suchevent, the Expiration Date with respect to such Warrant shall be the date onwhich Party B receives such notice from Party A, and the related SettlementDate shall be as soon as reasonably practicable after receipt of such noticebut no more than three (3) Business Days thereafter (but in no event shall theSettlement Date occur prior to the date on which it would have otherwiseoccurred but for the provisions of this paragraph (a)); *provided* thatthe related Net Settlement Amount shall be the same as the Net SettlementAmount but for the provisions of this paragraph (a).

(2)  **ConversionExercise Condition**. Party A may not exercise any Warrant hereunder, andAutomatic Exercise shall not apply with respect thereto, unless and until aConversion Event occurs on or after the Settlement Cutoff Date (in which casesuch condition shall be deemed to be satisfied with respect to a number of Warrants equal to the total Number of Warrants multiplied by the related Expiration Ratio).  "**Expiration Ratio**"means, with respect to any Conversion Event, the ratio of (a) the principalamount of Reference Notes converted in connection therewith to (b) thetotal principal amount of Reference Notes originally issued.

(b)        **ConversionNotices, Etc.**  If the Issuer receivesnotice of a conversion of the Convertible Notes due January 1, 2024(the "**Maturity Date**"), first putable January 1, 2009with an original principal amount of $150,000,000 (such Notes, the "**Reference Notes**",the Indenture under which such Reference Notes are issued, the "**Reference Indenture**", and such conversion a "**Conversion Event**"), then it shall promptly (and in any eventwithin two Business Days following the date on which the Issuer receives suchconversion notice provide a written notice to Party A, through the Agent,specifying the details of such event, including the principal amount ofReference Notes being converted and the related conversion settlementdate.  The Issuer further covenants toParty A that it shall promptly notify Party A of each Amendment Event(including in such notice a detailed description of any such amendment) andRepayment Event (identifying in such notice the nature of such Repayment Eventand the principal amount of Reference Notes being paid).  The Issuer hereby acknowledges and agrees thatits obligations under this paragraph shall continue notwithstanding anytransfer by it of any of its rights or obligations to any other person orentity in accordance with Section 8 below.

4.         **Deliveryof Shares**:

Subject to Section 9 below, if Party B is obligated todeliver Shares to Party A pursuant to the terms of this Confirmation(including, for the avoidance of doubt, pursuant to Section 5(c) hereof), PartyB may elect to deliver such Shares in accordance with any of the following:

(a)        if, in the reasonable determination of Party B, such Shares canbe delivered such that they may be sold free of any limitation on transferimposed by reason of material contractual limitations imposed on Party B andmay be sold by Party A after such delivery in the United States without anyregistration under the Securities Act of 1933, as amended (the "**SecuritiesAct**") and without volume limitations or restrictions on the mannerof sale, then Party B shall at the time of such electiondeliver an opinion of counsel (from counsel reasonably acceptable to Party Aand in form and substance reasonably satisfactory to Party A) confirming thatsuch Shares after delivery may be sold free of any limitation on transferimposed by reason of material contractual limitations imposed on Party B andmay be sold by Party A after such delivery in the United States without anyregistration under the Securities Act and without volume limitations orrestrictions on the manner of sale, then Party B may deliver such Shares toParty A without compliance with the procedures set forth on Appendix A orAppendix B hereto; *provided* that, if no opinion is delivered toParty A in accordance with this paragraph (a), then Party B shall deliver suchShares in accordance with paragraph (b) or (c) below;

(b)        Party B may register such Shares andotherwise satisfy each of the terms and procedures set forth on Appendix Ahereto (a "**Registered Offering**") and deliver suchShares pursuant to such Registered Offering; *provided*that if no suchRegistered Offering is effected, Party A shall deliver such Shares inaccordance with the procedures set forth on Appendix B hereto; or

(c)        Party B may, or if Party B is unable todeliver such Shares pursuant to the terms of paragraphs (a) and (b) above,shall, deliver such Shares pursuant to an offering that is exempt from theregistration requirements of the Securities Act, andthat shall otherwise comply with the terms and procedures (including theobligation, if applicable, to deliver additional Shares) set forth on AppendixB hereto (an "**Exempt Offering**").

5.         **Dischargeof certain payment obligations**:

Subject to Section 9 below:

(a)        For the purposes of this Section 5 theterms of Section 9.7 of the Equity Definitions shall be deemed to apply to thisTransaction.

(b)        If Party B shall owe Party A any amount pursuantto Section 9.7 of the Equity Definitions (except in the event of aNationalization, an Insolvency or a Merger Event in which the mergerconsideration to be paid to holders of Shares consists solely of cash) orpursuant to Section 6 of the Agreement (except in the event of an Event ofDefault, other than by virtue of Bankruptcy, with respect to which Party Bis the Defaulting Party) (in any such case, such amount owed shall be a "**PaymentObligation**"), then Party B may elect to satisfy such Payment Obligationby delivering to Party A, through the Agent, Shares.  If Party B fails to communicate such electionto Party A by such time, it shall be deemed that Party B did not make suchelection and the terms of Section 9.7 of the Equity Definitions or of Section6 of the Agreement, as the case might be, will apply.

(c)        If Party B makes such election, thenShares with a value (determined by the Calculation Agent acting to maximize theproceeds of the sale thereof (net of any fees and commissions, including withoutlimitation, underwriting or placement fees at the time of such sale)) equal tothe amount of the Payment Obligation described in paragraph (b) above shall bedelivered in accordance with Section 4 of this Confirmation (and, ifapplicable, the terms set forth on Appendix A or Appendix B hereto, asapplicable, shall apply *mutatis mutandis*); *provided*that forpurposes of such application: (i) any deliveries in respect thereof shallbe made on the date of payment or delivery required by Section 9.7 of theEquity Definitions or Section 6 of the Agreement, as the case may be; and (ii)the Final Resale Date, in the case of an Exempt Offering, shall be the secondExchange Business Day immediately following such date of delivery.  For the avoidance of doubt, Section 6 of thisConfirmation shall apply to any discharge of a Payment Obligation pursuant tothis Section 5.

6.         **MaximumNumber of Shares to be Delivered**:

            Subject to Section 9 below, the maximum number of Sharesthat Party B shall be required to deliver to Party A in relation to thisTransaction shall be equal to two times theNumber of Warrants (the "**Maximum Number of Shares to beDelivered**").

7.         **Additional Agreements of the Parties**:

Subject to Section 9below:

(a)        In the event of the bankruptcy of Party B (if it is theIssuer), Party A agrees that (1) Party A shall not have rights orassert a claim in respect of this Transaction that is senior in priority to therights and claims available to the shareholders of the common stock of Party B,and (2) Party A shall not set off any claim in respect of this Transactionagainst any amounts owing by Party A to Party B under any other transactionbetween the parties.

(b)        The parties acknowledge that thisTransaction is not secured by any collateral that would otherwise secure theobligations of Party B herein pursuant to the Agreement.  Without limiting the generality of theforegoing, this Transaction will not be considered to create obligationscovered by any collateral credit support annex to the Agreement and will bedisregarded for the purposes of calculating any exposures pursuant to any suchannex.

8.         **Transfer**:

(a)        Notwithstanding Section 7 of theAgreement, Party A may transfer its rights and obligations under thisTransaction at any time in its reasonable discretion (subject to any applicablefederal or state laws, regulations or other requirements).

(b)        Notwithstanding Section 7 of theAgreement, Party B may transfer its rights and obligations under thisTransaction with the consent of Party A (such consent not to be unreasonablywithheld), subject to any applicable federal or state laws, regulations orother requirements, and subject in all cases to Party A's standard creditapproval and compliance processes (including, without limitation, the executionand delivery by the transferee, if required by Party A, of a Credit SupportAnnex containing Party A's standard terms).

9.         **Applicabilityand Inapplicability of Certain Provisions**:

(a)        The second sentence of Section 3(b) of this Confirmationshall constitute a continuing obligation of the Issuer, and Sections 10(a) and(b) and Appendices A and B shall continue to apply to the Issuer,notwithstanding any transfer of its rights or other obligations in accordancewith Section 8 above.

(b)        Sections 4, 5, 6 and 7 of thisConfirmation shall not be applicable to Party B if Party B is not theIssuer or any of its affiliates.

10.        **AdditionalAgreements, Representations and Covenants of Party B, Etc.**:

(a)        Party Bhereby represents and warrants to Party A, on each day from the Trade Date toand including the date that is the earliest of (x) the date by which Party A isable to initially complete a hedge of its position created by this Transaction,(y) the date that is five (5) Exchange Business Days following the expirationof the period during which the Initial Purchaser is permitted to exercise itsoption to purchase additional Reference Notes, and (z) the date that is five(5) Exchange Business Days following the exercise by the Initial Purchaser ofits option to purchase additional Reference Notes, that:

(1)        itwill not, and will not permit any person or entity subject to its control to,bid for or purchase Shares during such period (in each case other than Sharespurchased from or through Party A); and

(2)        ithas publicly disclosed all material information necessary for it to be able topurchase or sell Shares in compliance with applicable federal securities lawsand that it has publicly disclosed all material information with respect to itscondition (financial or otherwise).

(b)        Each of Party A and Party B herebyagrees that from the Trade Date through to and including the Settlement Date,it will comply in all material respects with all corporate or, if applicable,similar laws affecting its ability to perform its obligations under thisTransaction, including any such requirements of the Commission or anyapplicable law.

(c)        Each of Party A and Party B herebyrepresents and warrants that (1) it has all necessary corporate power andauthority to execute, deliver and perform its obligations in respect of thisTransaction; such execution, delivery and performance have been duly authorizedby all necessary corporate action on its part; and this Confirmation has beenduly and validly executed and delivered by it and constitutes its legal, validand binding obligation, enforceable against it in accordance with its terms;and (2) neither the execution and delivery of this Confirmation nor theincurrence or performance of obligations of it hereunder will conflict with orresult in a breach of, or require any consent under, the certificate ofincorporation or by‐laws (or any equivalent documents) of it, or anyapplicable law or regulation, or any order, writ, injunction or decree of anycourt or governmental authority or agency, or any agreement or instrument towhich it or any of its affiliates is a party or by which it or any of itsaffiliates is bound or to which it or any of its affiliates is subject, orconstitute a default under, or result in the creation of any lien under, anysuch agreement or instrument.

(d)        If the Initial Purchaser party to thePurchase Agreement (as defined below) exercises its right to receive additionalReference Notes pursuant to the Initial Purchaser's option to purchaseadditional Reference Notes, then Party A and Party B will (i) enter into aconfirmation for a Warrant on substantially identical terms, including pricing,to this Confirmation with respect to such additional Reference Notes or (ii)amend this Confirmation to provide for such increase in Reference Notes (suchadditional confirmation or amendment to this Confirmation to provide for thepayment by Party A to Party B of the additional premium related thereto).

(e)        Party B shall deliver an opinion ofcounsel to Party A in form and substance satisfactory to Party A and Party B.

(f)        If an event occurs that results in a putof any Reference Notes to the Issuer by the holders thereof pursuant to theterms of the Reference Indenture (other than in connection with a Repayment Event),then this Transaction shall terminate automatically in respect of the number of Warrants whose ratio to thetotal Number of Warrants is equal to the ratio of the principal amount ofReference Notes that cease to be outstanding in connection with or as a resultof such event to the total principal amount of Reference Notes originallyissued (and, for the avoidance of doubt, if the principal amount of ReferenceNotes that cease to be outstanding is less than the total principal amountoutstanding of Reference Notes, then the terms of this Transaction shallcontinue to apply, subject to the terms and conditions set forth herein).

(g)        The parties hereby agree that alldocumentation with respect to this Transaction is intended to qualify thisTransaction as an equity instrument for purposes of EITF 00-19.  

(h)        Party A hereby agrees that from theTrade Date through to and including each Settlement Date, it will:

(1)        use its reasonable efforts to not becomean "affiliate" of Party B as such term is defined in Regulation144(a)(1) under the Securities Act;

(2)        not vote any Shares, as to which it has the right to exercisea vote; and

(3)        not permit any director, officer,employee, agent or affiliate to serve as a member of the board of directors ofParty B.

11.        **AdditionalTermination Events**:

            The occurrence of the following shall be AdditionalTermination Events with respect to Party B (which shall be the sole AffectedParty and this Transaction shall be the sole Affected Transaction):

(a)        the transactions contemplated by thePurchase Agreement among the Issuer and Credit Suisse First Boston LLC, asInitial Purchaser, dated as of December 17, 2003 (the "**PurchaseAgreement**") relating to the purchase of the Reference Notes shallfail to close as a result of any breach by the Issuer of its obligationsthereunder or as a result of any action, or failure to act, by the Issuerthereunder, in which case the entirety ofthis Transaction shall terminate automatically (and, for purposes ofdetermining Loss in relation to any such Additional Termination Event, it shallbe assumed that all conditions to the exercise of the Warrants have occurred);

(b)        a Conversion Event occurs prior to the Settlement CutoffDate, which shall constitute an Additional Termination Event in respect of theportion of this Transaction covering anumber of Warrants equal to the total Number of Warrants *multiplied by*the ratio of (1) the principal amount ofReference Notes converted in connection therewith to (2) the totalprincipal amount of Reference Notes originally issued (and, for the avoidance of doubt, if theprincipal amount of Reference Notes that cease to be outstanding as a result ofsuch Conversion Event is less than the total principal amount outstanding ofReference Notes, then the terms of this Transaction shall continue to applywith respect to the remaining Warrants hereunder, subject to the terms andconditions set forth herein);

(c)        an Amendment Event occurs, in which case the entirety of this Transactionshall terminate automatically; or

(d)        a Repayment Event occurs, in which case this Transaction shallterminate automatically in respect of the number of Warrants whose ratio to thetotal Number of Warrants is equal to the ratio of the principal amount ofReference Notes that cease to be outstanding in connection with or as a resultof such Repayment Event to the total principal amount of Reference Notesoriginally issued (and, for the avoidance of doubt, if the principal amount ofReference Notes that cease to be outstanding is less than the total principalamount outstanding of Reference Notes, then the terms of this Transaction shallcontinue to apply, subject to the terms and conditions set forth herein).

Inaddition, if the transactions contemplated by the Purchase Agreementshall fail to close for any reason other than those set forth in clause (a)above, then the entirety of thisTransaction shall terminate automatically and no payments shall berequired hereunder.       

For purposes of determining Loss inrelation to any such Additional Termination Event, it shall be assumed that allconditions to the exercise of the Warrants have occurred.

As used in this Section 11:

                        "**Amendment Event**"means that the Issuer amends, modifies, supplements or waives any term of theReference Indenture or the Reference Notes if such amendment, modification,supplement or waiver has a material effect on this Transaction or Party A'sability to hedge all or a portion of this Transaction, with such materialitydetermination to be made in the reasonable discretion of the Calculation Agent.

"**RepaymentEvent**" means that (a) any Reference Notes are repurchased orredeemed (in each case whether in connection with or as a result of a change ofcontrol, howsoever defined,  or for anyother reason other than on scheduled repurchase dates) by the Issuer, (b) anyReference Notes are delivered to the Issuer in exchange for delivery of anyproperty or assets of the Issuer or any of its affiliates (howsoeverdescribed), (c) any principal of any of the Reference Notes is repaidprior to the Maturity Date (whether following acceleration of the ReferenceNotes or otherwise), or (d) any Reference Notes are exchanged by or forthe benefit of the holders thereof for any other securities of the Issuer orany of its affiliates (or any other property, or any combination thereof)pursuant to any exchange offer or similar transaction.

12.        **Mattersrelating to the Agent**:

(a)        Credit Suisse First Boston, New Yorkbranch, in its capacity as Agent will be responsible for (i) effecting thisTransaction, (ii) issuing all required confirmations and statements to Party Aand Party B, (iii) maintaining books and records relating to this Transactionin accordance with its standard practices and procedures and in accordance withapplicable law and (iv) unless otherwise requested by Party B, receiving,delivering, and safeguarding Party B's funds and any securities in connectionwith this Transaction, in accordance with its standard practices and proceduresand in accordance with applicable law.

(b)        Agent is acting in connection with thisTransaction solely in its capacity as Agent for Party A and Party B pursuant toinstructions from Party A and Party B. Agent shall have no responsibility or personal liability to Party A orParty B arising from any failure by Party A or Party B to pay or perform anyobligations hereunder, or to monitor or enforce compliance by Party A or PartyB with any obligation hereunder, including, without limitation, any obligationsto maintain collateral.  Each of Party Aand Party B agrees to proceed solely against the other to collect or recoverany securities or monies owing to it in connection with or as a result of thisTransaction.  Agent shall otherwise haveno liability in respect of this Transaction, except for its gross negligence orwillful misconduct in performing its duties as Agent.

(c)        Any and all notices, demands, orcommunications of any kind relating to this Transaction between Party A andParty B shall be transmitted exclusively through Agent at the followingaddress:

Credit Suisse First Boston, New York branchEleven Madison AvenueNew York, NY 10010-3629

For payments and deliveries:Facsimile No.: (212) 325 8175Telephone No.: (212) 325 8678 / (212) 325 3213

For all other communications:Facsimile No.: (212) 325 8173Telephone No.: (212) 325 8676 / (212) 538 5306 /(212) 538 1193 / (212) 538 6886

(d)        The date and time of the Transactionevidenced hereby will be furnished by the Agent to Party A and Party B uponwritten request.

(e)        The Agent will furnish to Party B uponwritten request a statement as to the source and amount of any remunerationreceived or to be received by the Agent in connection with the Transactionevidenced hereby.

(f)        Party A and Party B each represents andagrees (i) that this Transaction is not unsuitable for it in the light of suchparty's financial situation, investment objectives and needs and (ii) that itis entering into this Transaction in reliance upon such tax, accounting,regulatory, legal and financial advice as it deems necessary and not upon anyview expressed by the other or the Agent.

13.        **AccountDetails**: 

                       Paymentsto Agent:                   The Bank ofNew York                                                                       Swift:    IRVTUS3N                                                                       A/C:     Credit Suisse First Boston                                                                        A/C#:   8900374179

                        Paymentsto Party A:                To be advised

                        Paymentsto Party B:                 To be advised

                        Deliveriesto Party B:                To be advised

Credit Suisse First Boston International is regulated by TheFinancial Services Authority and has entered into this Transaction asprincipal.  The time at which this Transactionwas executed will be notified to Party B (through the Agent) on request.

Please confirm that the foregoing correctly sets forth theterms of your agreement by signing and returning this Confirmation.

Yours faithfully,

CREDIT SUISSE FIRST BOSTON, acting through its New York branch and solely inits capacity as Agent

By:  /S/THOMAS DECKERName:  Thomas DeckerTitle:  Vice President Operations

By:  /S/AUGUSTINE VARGETTOName:  Augustine VargettoTitle:  Director Operations 

Confirmed as of the date first written above:

MENTOR CORPORATION (**PartyB**)

By:  /S/ADEL MICHAELName:  Adel MichaelTitle:  CFO

CREDIT SUISSE FIRST BOSTON INTERNATIONAL (**Party A**)

By:  /S/ANDREW WALTONName:  Andrew WaltonTitle:  Attorney-in-Fact

By:  /S/NICK HORNSEYName:  Nick HornseyTitle:  Attorney-in-Fact

----

APPENDIX Ato theCONFIRMATIONof aTRANSACTIONbetweenCREDIT SUISSE FIRSTBOSTON INTERNATIONALandMENTOR CORPORATION

Terms andProcedures Relating to a Registered Offering

The termsand procedures relating to a Registered Offering are as follows:

(a)        Prior to the beginning of the relevantReference Price Period, Party B shall file with the United States Securitiesand Exchange Commission (the "**Commission**") pursuant to the Securities Act aregistration statement on Form S-3 (or any successor form thereto) or suchother form as is acceptable to Party A and Party B, in respect of at least anumber of Shares sufficient to cover the number of Shares to be sold in respectof this Transaction, including a number of Shares equal to the Maximum Numberof Shares to be Delivered; such registration statement shall have been declaredeffective with respect to such Shares (the "**Registration Statement**") and no stop order suspendingthe effectiveness of the Registration Statement shall be in effect, and noproceedings for such purpose shall be pending before or threatened by theCommission.

(b)        To the extent required to effect suchRegistered Offering, Party A will use reasonable efforts, and shall usereasonable efforts to cause any Selling Agent engaged by Party A and anyunderwriter(s), to cooperate with Party B in order to comply in all materialrespects with the Registration Procedures. "**Selling Agent**" shall mean a broker dealerregistered with the Commission under Section 15 of the Securities Exchange Actof 1934, as amended (the "**Exchange Act**"), and forpurposes of this Transaction, the Selling Agent may also be an underwriter.

(c)        Party B shall have reserved and haveavailable, free from pre-emptive rights, out of its authorized but unissuedcapital stock the number of Shares of Capital Stock that would be issuable withrespect to such payment, for the purpose of effecting the delivery of anyamount of Shares due from Party B as provided in the Confirmation. 

(d)        PartyB, at the request of Party A, shall deliver an underwriting agreement oncommercially reasonable terms, naming Party A, or its designee, as underwriter,together with such other agreements, certificates and instruments as Party Amay reasonably require either pursuant to such underwriting agreement or as arecustomarily provided together with such underwriting agreement.

(e)        Party B shall have registered andqualified such Shares under such securities or "blue sky" laws ofsuch States and other jurisdictions in the United States of America and PuertoRico as Party A or any underwriter shall have reasonably requested, and shallhave done any and all other acts and things as may be reasonably necessary tobe done by Party B to enable Party A or any underwriter to consummate thedisposition in such jurisdictions of the Shares covered by the RegistrationStatement; *provided*thatParty B shall not be required to make any filing or take any action as a resultof this paragraph (e) that would require Party B to qualify as a foreigncorporation or file a general consent to service of process in anyjurisdiction.

(f)        Party B shall have caused such Sharesand the issuance thereof to be registered with or approved by such othergovernmental agencies or authorities in the United States of America as may bereasonably necessary to be done by Party B to enable Party A or any underwriterto consummate the disposition of such Shares.        

(g)        Party B shall have (i) given Party A andits underwriter(s), if any, and their respective counsel and accountants, theopportunity to participate in the preparation of all materials filed with theCommission pursuant to the requirements of either the Securities Act or theExchange Act or any other governmental agency (the "**Filed Materials**") prior to the first day of a saleperiod (a "**Sale Period**"),(ii) furnished to each of them copies of all such Filed Materials (and alldocuments incorporated therein by reference) sufficiently in advance of filingto provide them with a reasonable opportunity to review such documents andcomment thereon, (iii) given each of them such access to its books and recordsand such opportunities to discuss the business of Party B with its officers andthe independent public accountants who have issued a report on its financialstatement as shall be reasonably necessary, in the opinion of Party A and suchunderwriter(s) or their respective counsel, to conduct a reasonableinvestigation (within the meaning of the Securities Act) with respect to suchFiled Materials, (iv) delivered to Party A and its underwriter(s), if any, thefinancial statements of Party B filed with the Commission, (v) included in suchFiled Materials material, furnished to Party B in writing, which in thereasonable judgment of Party A or its underwriter(s), if any, subject to theconsent of Party B (which shall not be unreasonably withheld), should beincluded with respect to Party A, Party A's underwriter(s) and the "Planof Distribution", including, without limitation, language to the effectthat the holding by Party A of the Shares is not to be construed as arecommendation by Party A of the investment quality thereof and (vi) ifrequested by Party A, deleted from such Filed Materials any reference to PartyA by name or otherwise if in the written opinion of counsel to Party A,acceptable in form and substance to Party B, such reference to Party A byname or otherwise is not required by the Securities Act or any similar Federalstatute or applicable law then in force.

(h)        Party B shall have furnished to Party Aand any underwriter, addressed to Party A and any such underwriter and datedthe first day of the Sale Period, (i) an opinion of counsel for Party B (whichopinion may be from internal counsel for Party B) and (ii) a "coldcomfort" letter signed by the independent public accountants who haveissued a report on Party B's financial statements included in such RegistrationStatement, each in form and substance satisfactory to Party A and any suchunderwriter and their respective counsel covering substantially the same matterswith respect to such Shares and the offering, sale and issuance thereof and thefinancial statements of Party B as are customarily covered in opinions ofissuer's counsel and in accountants' letters delivered to underwriter(s) inunderwritten public offerings of securities and, in the case of theaccountants' letter, such other financial matters as Party A may havereasonably requested.

(i)         Party B shall have complied with allapplicable provisions of the Securities Act and the Exchange Act, all applicablerules of the Commission and all other applicable laws, rules and regulations ofany governmental or regulatory authority with respect to such Filed Materialsand such Shares and the offering, sale and issuance thereof.

(j)         Party B shall have caused all suchShares to be listed on the Exchange and on each securities exchange on whichsimilar securities issued by Party B are then listed.

(k)        Party B shall have provided a transferagent and registrar for such Shares.

(l)         Party B shall have taken such otheractions as Party A or any underwriter of such Shares shall have reasonablyrequested in order to expedite or facilitate the disposition of such Shares.

(m)       Party B shall provide Party A and itsunderwriter(s), if any, with indemnity and contribution in form and substancereasonably acceptable to Party A covering such matters relating to the Shares,the Filed Materials, and such other matters as Party A shall reasonablyrequest. 

(n)        Party B shall have paid all customarycosts and expenses reasonably incurred in connection with the foregoing,including, but without limitation, all underwriting fees relating to the saleof the Shares.

(o)        Party Bshall deliver all such registered Shares through the Clearance System.

(p)        If Party B is not the Issuer, thenreferences above in this Appendix A to Party B shall be deemed to be referencesto the Issuer as necessary, and Party B agrees to use its best efforts tocomply with the Registration Procedures set forth above.

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APPENDIX Bto theCONFIRMATIONof aTRANSACTIONbetweenCREDIT SUISSE FIRSTBOSTON INTERNATIONALandMENTOR CORPORATION

Terms andProcedures Relating to an Exempt Offering

The terms and procedures relating to an Exempt Offering areas follows:

(a)        The Calculation Agent shall determine theNet Settlement Amount with respect to the related Expiration Date in accordancewith the Settlement Terms set forth in the Confirmation.

(b)        On the Business Day following the end ofthe Reference Price Period, Party B shall deliver to Party A, in accordancewith the other provisions of this Appendix B, the number of shares thatthe Calculation Agent reasonably estimates to be the number of Shares that willproduce Net Proceeds (as defined below) at least equal to such Net SettlementAmount.

(c)        Party A, through the Selling Agent orany underwriter(s), shall sell all, or such lesser portion as may be requiredhereunder, of such Shares.

The proceeds of each sale inaccordance with this Appendix B, net of any fees and commissions (including,without limitation, underwriting or placement fees), together with carryingcharges and expenses incurred in connection with such offer and sale of theShares (including, but without limitation to, the covering of anyover-allotment or short position (syndicate or otherwise)) are referred to the"**Net Proceeds**" of such sale, in each case, customaryfor similar transactions under the circumstances at the time of such sale.

If the aggregate Net Proceeds ofall such sales is less than the Net Settlement Amount for such Expiration Date,then:

(1)        on the date on which Party A determinesthat there was a shortfall (the "**Shortfall Determination Date**")Party A shall notify Party B of the amount of such shortfall and provideevidence of the same to Party B;

(2)        on the Exchange Business Day nextsucceeding the Shortfall Determination Date (the "**Election Date**"),Party B shall deliver to Party A, through the Agent, a notice of its electioneither to pay to Party A, through the Agent, an amount in U.S. Dollars equal tosuch shortfall or to deliver to Party A, through the Agent, additional Shares;

(3)        if Party B so elects to pay Party A suchshortfall, then on the Currency Business Day next succeeding the Election DateParty B shall pay to Party A, through the Agent, an amount in U.S. Dollarsequal to such shortfall; and

(4)        if Party B so elects to deliveradditional Shares, then on the first Clearance System Business Day followingthe Election Date Party B shall deliver to Party A, through the Agent,additional Shares (meeting the conditions specified herein with respect to theShares initially delivered to Party A under paragraph (b) above) in such numberas the Calculation Agent reasonably estimates to be the number of Shares thatwill produce Net Proceeds at least equal to such shortfall, and thereafterParty A, through the Selling Agent or any underwriter(s), shall sell all, orsuch lesser portion as may be required hereunder, of such Shares.

The provisions of this paragraph(c) shall be repeated with respect to such additional Shares until theaggregate Net Proceeds from the sales of all Shares delivered by Party B underparagraph (b) above and this paragraph (c) shall be at least equal to the NetSettlement Amount for such Expiration Date (with the date on which the finalsale of Shares occurs being referred to herein as the "**Final ResaleDate**" for such Expiration Date), *provided*that the aggregate number of Sharessold pursuant to this Appendix B with respect to all Expiration Dates shall notexceed the Maximum Number of Shares to be Delivered.

Party A shall retain all NetProceeds of all such sales, *provided*that if the aggregate Net Proceeds of all such sales exceeds theNet Settlement Amount for such Expiration Date, then Party A will refund suchexcess to Party B in U.S. Dollars on the date that is three (3) CurrencyBusiness Days following such Final Resale Date. If any portion of the Shares delivered to Party A remains unsold afterthe Final Resale Date, then Party A shall return such unsold Shares to Party Bon such Final Resale Date.

(d)        Party B agrees to comply with thereasonable requests of Party A, the Selling Agent, any placement agent and anypurchaser of the Shares, and Party A agrees to use commercially reasonablemeans to effect each offer and sale of Shares at commercially reasonable pricesin light of the market conditions and the circumstances of Party B at the timeof such offer and sale.  Party B herebyacknowledges that any Shares sold pursuant to an Exempt Offering may be sold atprices that are less than the prices that may otherwise be available if suchShares were to be sold pursuant to a registered public offering or at pricesobserved in the secondary market.

(e)        Neither Party A nor the Selling Agent nor any other partyshall have any obligation to commence any offer and sale of any Shares inrespect of an Exempt Offering until such conditions as any purchasers or theSelling Agent, or their respective counsel, may reasonably require to complywith any laws or regulations directly applicable to the offer and sale of theshares are satisfied.  

(f)        For purposes of this Appendix B, the NetSettlement Amount shall be deemed to be the Net Settlement Amount (determinedas provided in the Confirmation to which this Appendix B is attached) plus anadditional amount (determined from time to time by the Calculation Agent in itscommercially reasonable judgment) attributable to interest that would be earnedon such Net Settlement Amount (increased on a daily basis to reflect theaccrual of such interest and reduced from time to time by the amount of NetProceeds received by Party A as provided herein) at a rate equal to the openFederal Funds Rate plus the Spread for the period from, and including, suchSettlement Date to, but excluding, the related Final Resale Date and calculatedon an Actual/360 basis.  The foregoingprovision shall be without prejudice to Party A's rights under the Agreement(including, without limitation, Sections 5 and 6 thereof).

            As used in this paragraph (f),"**Spread**" means, with respect to any Net SettlementAmount, the credit spread over the applicable overnight rate that would beimposed if Party A were to extend credit to Party B in an amount equal to suchNet Settlement Amount, all as determined by the Calculation Agent using its commerciallyreasonable judgment as of the related Settlement Date.  Commercial reasonableness shall take in toconsideration all factors deemed relevant by the Calculation Agent, which areexpected to include, among other things, the credit quality of Party B (andany relevant affiliates) in the then-prevailing market and the credit spread ofsimilar companies in the relevant industry and other companies having asubstantially similar credit quality.

(g)        If Party B is not the Issuer, referencesabove in this Appendix B to Party B shall be deemed to be references to theIssuer as necessary, and Party B agrees to use its best efforts to comply withthe Registration Procedures set forth above.