**Exhibit10.611**

 
|        |   | Chiron Corporation

4560 Horton Street

Emeryville, California  94608-2916

510.655.8730 |
|--------|--------|------------------------------------------------------------------------------------------|
|   |
|   |
|   |

 

October 24, 2000

 

**CONFIDENTIAL**

 

Gene Walther[Residence address]

 

Dear Gene:

 

We are pleased to confirmour offer of employment for you to join Chiron Corporation.

 

Chiron’s mission is tohave power over disease – to use biotechnology as a tool for preventing andtreating illnesses. We are counting on you to help us with this work.

 

Your employment offerwith Chiron is as DVP, Commercial Development, Blood Testing reporting to meinitially. Your starting salary will be paid at a bi-weekly rate of $6,923.08($180,000 annually) as an exempt employee.

 

In addition, you willreceive a $30,000.00 hiring bonus upon initiation of your employment withChiron. This bonus will appear in your first paycheck.

 

You will also be eligiblefor Chiron’s relocation assistance program. Cathy Gannon, who administers theprogram, can provide you with additional details of Chiron’s employeerelocation program. Cathy’s telephone number is 203-926-2404 and her e-mailaddress is catherine.gannon@prudential.com

 

You will be eligible toparticipate in our stock option program. Subject to the approval of the Boardof Directors, you will be awarded a stock option grant of 20,000 options topurchase Chiron common stock. The options vest fully over a four-year period,with the first 25% of the shares vesting at the one-year grant anniversary.Shares vest on a pro-rated monthly basis over the subsequent remaining threeyears of the vesting period. The exercise price of the option will be set atthe fair market value (as defined in the Option Plan) of a share of Chironstock on the date the option is approved. We expect the options will beapproved and effective within 90 days of your employment date.

 

You will also be eligibleto participate in Chiron’s Annual Incentive Plan (AIP). The Plan linkscorporate, business/functional unit and individual performance metrics tosupport the accomplishment of Chiron’s business goals. The Plan, as structured,has an incentive range for your position from 0% to 60% with a target of 30% ofbase pay. Plan participants hired between October 1 and December 30, 2000 willbe eligible to participate in the 2001 plan year. The AIP award, if earned, ispaid in the first quarter of 2002.

 

The information sheetsfollowing your offer letter contain some of the highlights of Chiron’s benefitsprograms. You should note that, while this offer is being made under the termsof our current benefits and compensation programs, changes do occur from timeto time and any system-wide changes that occur will apply to you as well.

 

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Some of these programsare effective immediately upon your employment, while others are dependent uponestablished enrollment periods. Your group medical insurance benefits generallystart on the first day of the month ***following***your date of hire. If, however,your date of hire is the first business day of the month, your coverage becomeseffective on that date. Note also that, with few exceptions, Chiron extendsbenefits coverage to qualified family members, including opposite- and same-sexdomestic partners. You will have an opportunity to learn more about yourbenefits and complete the enrollment paperwork at a benefits orientation heldtwice a month. The schedule will be provided for you at new hire orientation.

 

As a part of Chiron’sroutine medical surveillance program, employees with certain projectassignments may be advised to provide a baseline blood sample for archivalstorage. The Chiron Occupational Health Department will notify you if abaseline blood draw is recommended.

 

This offer is contingentupon your ability, as required by federal law, to establish your employmenteligibility as a U.S. citizen, a U.S. lawful permanent resident, or anindividual specifically authorized for employment in the U.S. by theImmigration and Naturalization Service. Please read the enclosed noticespecifying the documentation required in this regard. ***Please bring any requireddocumentation to new hire orientation.*** If you have an employmentauthorization document (EAD) issued by the Immigration and NaturalizationService, please contact Inverleith Fruci in Emeryville, California at (510)923-2516.

 

Under California law,employment with Chiron is not for any specified term and can be terminated atany time for any reason by you or Chiron. Any contrary representations whichhave been made or may be made to you are superseded by this offer. When youaccept the offer, the terms described in this letter and the Chiron EmployeeInvention and Confidential Information Agreement shall constitute the terms ofyour employment.

 

Gene, we hope the termsof this offer are satisfactory and we look forward to a favorable response. Ifyou have any questions in the meantime, please feel free to contact me. Again,we think Chiron’s challenge - power over disease - will require all of our bestefforts.

 

Sincerely,

 
| CHIRON CORPORATION        |
|---------------------------|
|                      |
| /s/ Rajen Dalal           |   |
| Rajen Dalal               |
| President, Blood  Testing |

 

Enclosures

 

cc:      Human Resources

 

2

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Please indicate yourunderstanding of the terms of this offer and your acceptance of this offer,along with your confirmed start date, by signing this letter and filling outthe attached packet of forms. **In order toexpedite the processing of your employment records, please return the letterand completed forms to the Chiron Human Resources Department in the enclosedpostage paid envelope as soon as possible.**Please keep the copy ofyour offer letter.

 

 
| /s/ Gene W. Walther |   | 17 Jan’01 |   | 22 January 2001      |
|---------------------|--------|----------------|--------|----------------------|
| Name                |   | Date           |   | Confirmed Start Date |

 

Please note that newEmployee Orientation for **Emeryville**-basedemployees is typically held every Monday and is scheduled from 9:00AM through3:00PM. Please meet in the lobby of the Life Sciences building at 5300 ChironWay. Enclosed is the Orientation Agenda. Parking is available in any of ourparking lots.

 

In preparation for yourarrival you will need to complete the packet of forms that is enclosed. **The completion of the forms in the packet is acondition of employment and required in order for you to be paid.**

 

If, for any reason, youare not able to attend your scheduled orientation session, or if your actualstart date is on a day other than a Monday, please contact Human Resourcesimmediately so that you are paid on a timely basis.

 

1.)     Seeattached letter from Rajen Dalal dated January 11, 2001.

 

2.)     Seeattached summary of January 14 telephone conversation.

 

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|        |   | Chiron Corporation

4560 Horton Street

Emeryville, California  94608-2916

510.655.8730 |
|--------|--------|------------------------------------------------------------------------------------------|
|   |
|   |
|   |

 

January 11, 2001

 

Mr. Gene W. Walther[Residence address]

 

Dear Gene:

 

This letter will serve asan addendum to your letter of employment from Chiron Corporation dated October24, 2000. There are three specific items you asked me to address. I sincerelyapologize for the delay in doing so.

 

First, there is thequestion of Susan Josey reporting to you. I believe we covered this during thelast Commercial Council meeting when we revised the organizational chart toindicate Susan’s solid line reporting relationship to you, and dotted linerelationship to me. I concur that this relationship makes sense initially, andsuggest we review this in the middle of the year. I will ask Joann to calendarthis.

 

Secondly, you haveimpressed upon me a strong desire to report directly to the President. Pleaseknow that this desire has been heard. The reporting relationship is in linewith our present structure, and it is my hope that, as you continue to definethe Division’s strategy with other members of the Commercial Council, you willparticipate in organizational design and development issues. I know you willagree that, in an environment such as ours, there will be high-levelrelationship issues that will evolve over time. One such issue is when to addthe position of World-wide Head of Marketing and Sales. If, and when, such aposition is created and filled, we will work with you to structure yourresponsibilities such that a direct reporting line to the President can bemaintained.

 

Third, I wish to addressyour request for participating in the NAT bonus program. For our mutual benefitand that of your relationship with other members of the team who have madedirect contributions to the success of this program, my preference would be tooffer you the following.  As a gesture ofgood faith, and in appreciation of your contributions, we would like to presentyou with an additional bonus in the amount of $50,000. This payment will bemade to you upon signing.

 

Lastly, Gene, we areeager to have you physically located in the Bay Area so you can participatefully as an executive member of the blood testing management, assuming allaspects of leadership required in this role. This offer assumes that you willmake the transition from Seattle to the Bay Area in 2001.

 

1

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Gene, if you have anyquestions regarding the content of this letter, please give me a call. I lookforward to our continued mutual success.

 

Best Regards,

 
| /s/ Rajen Dalal                    |   |
|------------------------------------|--------|
| Rajen Dalal                        |
| President, Blood  Testing Division |

 

RD:jw

 

cc:       InverleithFruci

 

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* See attached summary ofJanuary 14 telephone call.

 

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**InterofficeMemo**

 
| **Date:** | ** ** | **January  17, 2001**                           |
|-----------|------------|-------------------------------------------------|
|      |       |                                            |
| **To:**   | ** ** | **Rajen  Dalal**                                |
|      |       |                                            |
| **Cc:**   |       |                                            |
|      |       |                                            |
| **From:** | ** ** | **Gene Walther**                                |
|      |       |                                            |
| **RE:**   | ** ** | **Offer  Letter - Transition/Operational Plan** |

 

As we discussed on Sundaymorning, I had one concern regarding your letter dated January 11th.This issue was in regard to the timing of my transition from Seattle toEmeryville. We have agreed that my transition will occur in the later half of2002 rather than in 2001 as stipulated in your letter.

 

We also discussed theneed for my presence in Emeryville to provide leadership to the team and anoperational plan in this regard. I have suggested that we obtain a two-bedroomcorporate apartment to be shared by the field-based (male) personnel when inEmeryville. I have spoken with Chyang and he has agreed this would be agreeablewith him as well. Additionally, I will work with the Travel department toschedule flights well into the future (and perhaps throughout the entire year)in order to maximize the cost savings and obtain the lowest fares possible. (Whilethe actual dates are subject to change, due to my flight program status, thesechanges should not require additional charges.) We agreed that while I wouldnot be held to a specific amount of time in Emeryville, I will agree to balancemy time in Emeryville with my personal commitments as best I can.

 

I believe this addressesthe final issue with regard to my hire.

 
| /s/ Gene W. Walther |   |
|---------------------|--------|
| Gene W. Walther     |

 

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