Exhibit 10.514

CHIRON CORPORATION.
                            , 2002

Dear
Restricted Share Rights Holder:

I
am pleased to inform you that the Compensation Committee of the Board of Directors of Chiron Corporation (the "Company") recently approved an amendment to each of your outstanding
restricted share rights listed on Exhibit A (the "Share Rights") to provide you with greater protection in the event of certain corporate transactions.

The
amendment is set forth in detail below. In general terms, the amendment: (i) modifies the definition of "Cause" to provide you with additional protection in the event of your
termination under certain circumstances, (ii) provides that your Share Rights will automatically vest and be paid out in the event of a merger unless they are assumed by the acquiring company
and (iii) provides that your Share Rights will immediately vest upon a Qualifying Termination of your employment that occurs within twenty-four (24) months after a Change in
Control. (See below for definitions.)

Accordingly,
the restricted share rights letter agreement (the "Agreement) documenting your Share Rights is hereby amended to read as follows:

Corporate Transaction

If the Company or its stockholders enter into an agreement to dispose of all or substantially all of the assets of the Company, enter into an agreement to merge
or consolidate with another entity, or enter into a plan of reorganization or liquidation, while your restricted share rights are outstanding, then
each outstanding share right will become vested and paid in full, immediately before the consummation of such transaction. However, no acceleration of the vesting or payment date will occur if the
agreement requires as a prerequisite to the consummation of any such transaction that each such outstanding share right will be either assumed by the successor corporation or parent thereof or be
replaced with a comparable share right in the successor corporation or parent thereof.

Qualifying Termination Following a Change in Control

If there is a Change in Control of the Company pursuant to which the share rights continue and within twenty-four (24) calendar months
thereafter there is a Qualifying Termination of your employment, then these share rights will vest and will be paid out in full.

For
this Agreement, the following definitions apply:



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Notwithstanding
anything else contained herein (this Agreement) to the contrary, in no event shall a Change in Control be deemed to have occurred by reason of a purchase, or series of
purchases of Company stock by Novartis or its successor such that the acquiring entity remains subject to the terms of that certain Governance Agreement dated as of January 5, 1995, as amended
through December 9, 2000, provided the acquiring entity's Company stock holdings, direct or indirect, in the aggregate, represent less than seventy-nine and nine-tenths
of a percent (79.9%) of the combined voting power of all outstanding Company securities. In addition, in no event shall a Change in Control be deemed to have occurred, with respect to you, if you are
part of a purchasing group that consummates the Change-in-Control transaction. You shall be deemed "part of a purchasing group" for purposes of the preceding sentence if you
are an equity participant in the purchasing company or group (except for: (i) passive ownership of less than three percent (3%) of the stock or other equity of the purchasing company; or
(ii) ownership of equity participation in the purchasing company or group which is otherwise not significant, as determined prior to the Change in Control by a majority of the nonemployee
continuing Directors).



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However,
the occurrence of an event set forth in (i) through (iv) above shall not constitute Good Reason if the Company has cured such event within fifteen (15) days
of receipt of written notice from you that such event has occurred and constitutes Good Reason.

Except
for the foregoing change of the Agreement applicable to your Share Rights, no other terms or conditions of your Share Rights have been modified as a result of the amendment, and
those other terms and conditions will continue in full force and effect. Please attach a copy of this letter agreement to your original Agreement so that you will have a complete record of all the
terms applicable to your Share Rights.

The
amendment was effective as of February 16, 2001. We hope that you find this amendment a valuable addition to your equity package. Should you have any questions concerning the
amendment, please direct them to the undersigned.

| |  | Very truly yours, Chiron Corporation
| |  | ------------------------------------
| |  |                                     
| |  |                                     
| |  | By:                                 
| |  | Title:                              

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EXHIBIT A

Name

Date of Grant

Total Number of
Restricted Share
Rights


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